Problem Description: It used to use the IIS5.0 in Server2000, now popular Server2003, so change it. The problem came out, I used to have a component that I have compiled in IIS5.0. I didn't expect to go wrong. I found that I have a relationship with the file size, so I search on the Internet. It turns out that IIS6.0 default configuration puts upload files Limited in 200K, program: response.buffer = true formsize = request.totalbytes formData = request.binaryRead (Formsize) is wrong! Solution: First, stop the following services: Simple Mail Transfer Protocol (SMTP) World Wide Web Publishing Service FTP Publishing Service HTTP SSL HTTP SSL then edit: C: /Windows/system32/inesrv/metabase.xml / Windows / system32 / inesrv /metabase.xml Find: SpMaxRequestentityAllowed defaults to 204800 (200K), changed to need! Finally, start the service that is stopped, even if it is done! * Note: Maybe you can touch the Metabase.xml file cannot be saved, the reason is that your service is not clean, it is recommended to restart it later!